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ABCMATCH(1) DragonFly General Commands Manual ABCMATCH(1)
NAME
abcmatch - Search for specific sequences of notes in an abc file
composed of many tunes.
SYNOPSIS
abcmatch abc file [-c] [-v] [-r] [-con] [-fixed nn] [-qnt] [-lev]
[-a] [-ign] [-br %d] [-tp abc reference file] [-ver]
[-pitch_hist] [-wpitch_hist] [-length_hist] [-interval_hist]
[-pitch_table] [-interval_table] reference number
DESCRIPTION
abcmatch is used to search for specific sequences of notes in an abc
file composed of many tunes. For example, if you know a few bars of a
tune, you can use this program to find the tune having this sequence
and perhaps identify the tune. At a minimum, abcmatch requires two
files. A template file called match.abc which contains the bars that
you are searching for and a large file consisting of a hundred or more
abc tunes. The program automatically loads up the match.abc file and
then scans every tune in the large file
OPTIONS
-v and -c
mainly used for debugging when the program does not do what was
expected.
-ver prints version number and then exits
--norhythm
Causes the matching algorithm to ignore the length of notes in a
bar, thus E3/2F/D GA2 would match EFD G2A. The option ignores -r
parameter since it is now irrelevant.
-pitch_table
Used to produce a interval weighted pitch histogram for each
tune in the file. If this is saved in an external file, that
file could be used as a database for finding tunes with similar
pitch probability density functions (pdf).
-r Controls how the matching criterion handles small rhythm
variations in the melody. The -r option must be followed by a
number which specifies the temporal resolution for the match.
When the number is zero, this indicates that a perfect match
should be performed, meaning that the lengths of each note in
the bar must match exactly in order to be reported. For larger
values a looser match will be performed as described below. Note
lengths are converted into temporal units where a quarter note
normally is assigned a value of 24. Therefore an eight note has
a value of 12, a sixteenth has a value of 6, a half note has a
value of 48 and etc. If you specify a temporal resolution of 12,
then the pitch values of the notes only need to match at time
units which are multiples of an eighth note.
-fixed n
Causes the program to disregard bar lines when does the
matching. It allows matching of notes between tunes having
different time signatures. n is a number which specifies the
exact number of notes to match. For example if n is 4, the
program could match |C E G E| .. with |C E|G E| Note the matcher
still starts at a beginning of a given bar for both the tune and
template.
-con Specifies contour matching. In this case, the program uses the
key signature only to indicate accidentals. The pitch contour is
computed from the pitch difference or interval between adjacent
notes.
-qnt Uses the contour matching algorithm but also quantizes the
intervals using the following table:
unison and semitone 0 minor 2nd to major 2nd 1 minor 3rd to
major 3rd 2 any larger interval 3
Negative numbers are descending intervals.
-tp file name, reference number
Substitute any tune for the template match.abc. When using this
feature, the entire tune is used as a template. Abcmatch does
not match the template with itself, and only bars which match
bars in other tunes are reported.
-br threshold
Runs the program in a brief mode designed to identify groups of
tunes sharing common bars. In this mode, the program counts the
numbers of bars in the test tune which are also present in
match.abc. If the number of common bars is larger or equal to
the threshold then the program reports the tune and the number
of common bars. The program scans all the tunes in the abc file
and returns a list of all the tunes which have more than a
specific number of bars in common with the template, match.abc.
In actual use, the program is run repeatedly by a script. For
each tune in a abc file, it creates a template file called
match.abc and then executes abcmatch. The outputs are displayed
on the screen in a form easy to interpret. The user has no
control of the matching criterion. The rhythm must match exactly
and the notes are transposed to suit the key signature. In other
words the -r parameter is independent of what is specified in
the parameter list.
-pitch_hist or -length_hist
Runs the program in another mode. It produces a histogram of the
distribution of the notes in the abc file. The pitch is
indicated in midi units. Thus middle C is 60 and the pitches go
up in semitone units. Following the pitch is a count of the
number of times that note occurred.
-pitch_table or -interval_table
Used to create a database for a collection of tunes in a file
for future analysis.
SEE ALSO
abc2abc(1), abc2midi(1), mftext(1) ,midi2abc(1) ,midicopy(1) ,yaps(1)
AUTHOR
This manual page was written by Ross Gammon based on abcmatch.txt by
Seymour Shlien.
VERSION
This man page describes abcmatch version 1.35 from January 15 2006.
ABCMATCH(1)